Thanks for the replies chaps...
Unfortunately no one in the UK has the correct parts for the Petrol starter, ( plenty in USA). Been told by Toyota, Milners and Roughtrax that the starter in the petrol is a different model and the bits will not fit. Srange as it's only 2 copper contacts. I assume the plunger diameter is different...
I need it sorted pronto, so I just ordered a replacement starter from Milners, and I have ordered the bits from the US which will arrive in 2-3 weeks. I'll repair the original and swap it back in as its a 2kw(cold version) starter and the Milners is a 1.4kw.